Changeset: 39 Move more things to source-common/

9 files changed, 2280 insertions, 0 deletions

diff --git a/source-common/Enum.hpp b/source-common/Enum.hpp
new file mode 100644
index 0000000..5e106fe
--- /dev/null
+++ b/source-common/Enum.hpp
@@ -0,0 +1,103 @@
+#pragma once
+
+#include <initializer_list>
+#include <type_traits>
+
+template <class TEnum>
+class EnumFlags {
+public:
+	using Enum = TEnum;
+	using Underlying = std::underlying_type_t<TEnum>;
+
+private:
+	Underlying mValue;
+
+public:
+	EnumFlags()
+		: mValue{ 0 } {
+	}
+
+	EnumFlags(TEnum e)
+		: mValue{ 1 << static_cast<Underlying>(e) } {
+	}
+
+	bool IsSet(EnumFlags mask) const {
+		return (mValue & mask.mValue) == mask.mValue;
+	}
+
+	bool IsSet(std::initializer_list<TEnum> enums) {
+		EnumFlags flags;
+		for (auto& e : enums) {
+			flags.mValue |= static_cast<Underlying>(e);
+		}
+		return IsSet(flags);
+	}
+
+	bool IsSetExclusive(EnumFlags mask) const {
+		return mValue == mask.mValue;
+	}
+
+	bool IsSetExclusive(std::initializer_list<TEnum> enums) {
+		EnumFlags flags;
+		for (auto& e : enums) {
+			flags.mValue |= static_cast<Underlying>(e);
+		}
+		return IsSetExclusive(flags);
+	}
+
+	void SetOn(EnumFlags mask) {
+		mValue |= mask.mValue;
+	}
+
+	void SetOff(EnumFlags mask) {
+		mValue &= ~mask.mValue;
+	}
+
+	void Set(EnumFlags mask, bool enabled) {
+		if (enabled) {
+			SetOn(mask);
+		} else {
+			SetOff(mask);
+		}
+	}
+
+	EnumFlags& operator|=(EnumFlags that) const {
+		mValue |= that.mValue;
+		return *this;
+	}
+
+	EnumFlags& operator&=(EnumFlags that) const {
+		mValue &= that.mValue;
+		return *this;
+	}
+
+	EnumFlags& operator^=(EnumFlags that) const {
+		mValue ^= that.mValue;
+		return *this;
+	}
+
+	EnumFlags& operator|=(TEnum e) const {
+		mValue |= 1 << static_cast<Underlying>(e);
+		return *this;
+	}
+
+	EnumFlags& operator&=(TEnum e) const {
+		mValue &= 1 << static_cast<Underlying>(e);
+		return *this;
+	}
+
+	EnumFlags& operator^=(TEnum e) const {
+		mValue ^= 1 << static_cast<Underlying>(e);
+		return *this;
+	}
+
+	EnumFlags operator|(EnumFlags that) const { return EnumFlags(mValue | that.mValue); }
+	EnumFlags operator&(EnumFlags that) const { return EnumFlags(mValue & that.mValue); }
+	EnumFlags operator^(EnumFlags that) const { return EnumFlags(mValue ^ that.mValue); }
+
+	EnumFlags operator|(TEnum e) const { return EnumFlags(mValue | 1 << static_cast<Underlying>(e)); }
+	EnumFlags operator&(TEnum e) const { return EnumFlags(mValue & 1 << static_cast<Underlying>(e)); }
+	EnumFlags operator^(TEnum e) const { return EnumFlags(mValue ^ 1 << static_cast<Underlying>(e)); }
+
+	EnumFlags operator~() const { return EnumFlags(~mValue); }
+};
diff --git a/source-common/PodVector.hpp b/source-common/PodVector.hpp
new file mode 100644
index 0000000..74e99d6
--- /dev/null
+++ b/source-common/PodVector.hpp
@@ -0,0 +1,297 @@
+// File adapted from dear-imgui's ImVector, implemented in https://github.com/ocornut/imgUI/blob/master/imgui.h
+#pragma once
+
+#include <cassert>
+#include <cstddef>
+#include <cstdint>
+#include <cstdlib>
+#include <cstring>
+#include <span>
+
+template <class T>
+class PodVector {
+public:
+	using value_type = T;
+	using iterator = value_type*;
+	using const_iterator = const value_type*;
+
+private:
+	int mSize;
+	int mCapacity;
+	T* mData;
+
+public:
+	PodVector() {
+		mSize = mCapacity = 0;
+		mData = nullptr;
+	}
+
+	PodVector(const PodVector<T>& src) {
+		mSize = mCapacity = 0;
+		mData = nullptr;
+		operator=(src);
+	}
+
+	PodVector<T>& operator=(const PodVector<T>& src) {
+		clear();
+		resize(src.mSize);
+		std::memcpy(mData, src.mData, (size_t)mSize * sizeof(T));
+		return *this;
+	}
+
+	PodVector(PodVector&& src) {
+		mSize = src.mSize;
+		mCapacity = src.mCapacity;
+		mData = src.mData;
+
+		src.mSize = src.mCapacity = 0;
+		src.mData = nullptr;
+	}
+
+	PodVector& operator=(PodVector&& src) {
+		if (this != &src) {
+			std::free(mData);
+
+			mSize = src.mSize;
+			mCapacity = src.mCapacity;
+			mData = src.mData;
+
+			src.mSize = src.mCapacity = 0;
+			src.mData = nullptr;
+		}
+		return *this;
+	}
+
+	~PodVector() {
+		std::free(mData);
+	}
+
+	bool empty() const { return mSize == 0; }
+	int size() const { return mSize; }
+	int size_in_bytes() const { return mSize * (int)sizeof(T); }
+	int max_size() const { return 0x7FFFFFFF / (int)sizeof(T); }
+	int capacity() const { return mCapacity; }
+
+	T& operator[](int i) {
+		assert(i >= 0 && i < mSize);
+		return mData[i];
+	}
+
+	const T& operator[](int i) const {
+		assert(i >= 0 && i < mSize);
+		return mData[i];
+	}
+
+	void clear() {
+		if (mData) {
+			mSize = mCapacity = 0;
+			std::free(mData);
+			mData = nullptr;
+		}
+	}
+
+	T* begin() { return mData; }
+	const T* begin() const { return mData; }
+	T* end() { return mData + mSize; }
+	const T* end() const { return mData + mSize; }
+
+	T* data() { return mData; }
+
+	T& front() {
+		assert(mSize > 0);
+		return mData[0];
+	}
+
+	const T& front() const {
+		assert(mSize > 0);
+		return mData[0];
+	}
+
+	T& back() {
+		assert(mSize > 0);
+		return mData[mSize - 1];
+	}
+
+	const T& back() const {
+		assert(mSize > 0);
+		return mData[mSize - 1];
+	}
+
+	void swap(PodVector<T>& rhs) {
+		int rhs_size = rhs.mSize;
+		rhs.mSize = mSize;
+		mSize = rhs_size;
+		int rhs_cap = rhs.mCapacity;
+		rhs.mCapacity = mCapacity;
+		mCapacity = rhs_cap;
+		T* rhs_mDataTmp = rhs.mData;
+		rhs.mData = mData;
+		mData = rhs_mDataTmp;
+	}
+
+	int grow_capacity(int sz) const {
+		int newCapacity = mCapacity ? (mCapacity + mCapacity / 2) : 8;
+		return newCapacity > sz ? newCapacity : sz;
+	}
+
+	void resize(int new_size) {
+		if (new_size > mCapacity) reserve(grow_capacity(new_size));
+		mSize = new_size;
+	}
+
+	void resize_more(int size) {
+		resize(mSize + size);
+	}
+
+	void resize(int new_size, const T& v) {
+		if (new_size > mCapacity) reserve(grow_capacity(new_size));
+		if (new_size > mSize) {
+			for (int n = mSize; n < new_size; n++) {
+				std::memcpy(&mData[n], &v, sizeof(v));
+			}
+		}
+		mSize = new_size;
+	}
+
+	void resize_more(int size, const T& v) {
+		resize(mSize + size, v);
+	}
+
+	void shrink(int new_size) {
+		assert(new_size <= mSize);
+		mSize = new_size;
+	}
+
+	/// Resize a vector to a smaller mSize, guaranteed not to cause a reallocation
+	void reserve(int newCapacity) {
+		if (newCapacity <= mCapacity) return;
+		auto tmp = (T*)std::malloc((size_t)newCapacity * sizeof(T));
+		if (mData) {
+			std::memcpy(tmp, mData, (size_t)mSize * sizeof(T));
+			std::free(mData);
+		}
+		mData = tmp;
+		mCapacity = newCapacity;
+	}
+
+	void reserve_more(int size) {
+		reserve(mSize + size);
+	}
+
+	/// NB: It is illegal to call push_back/push_front/insert with a reference pointing inside the PodVector data itself! e.g. v.push_back(v[10]) is forbidden.
+	void push_back(const T& v) {
+		if (mSize == mCapacity) reserve(grow_capacity(mSize + 1));
+		std::memcpy(&mData[mSize], &v, sizeof(v));
+		mSize++;
+	}
+
+	void pop_back() {
+		assert(mSize > 0);
+		mSize--;
+	}
+
+	void push_front(const T& v) {
+		if (mSize == 0) {
+			push_back(v);
+		} else {
+			insert(mData, v);
+		}
+	}
+
+	T* erase(const T* it) {
+		assert(it >= mData && it < mData + mSize);
+		const ptrdiff_t off = it - mData;
+		std::memmove(mData + off, mData + off + 1, ((size_t)mSize - (size_t)off - 1) * sizeof(T));
+		mSize--;
+		return mData + off;
+	}
+
+	T* erase(const T* it, const T* it_last) {
+		assert(it >= mData && it < mData + mSize && it_last > it && it_last <= mData + mSize);
+		const ptrdiff_t count = it_last - it;
+		const ptrdiff_t off = it - mData;
+		std::memmove(mData + off, mData + off + count, ((size_t)mSize - (size_t)off - count) * sizeof(T));
+		mSize -= (int)count;
+		return mData + off;
+	}
+
+	T* erase_unsorted(const T* it) {
+		assert(it >= mData && it < mData + mSize);
+		const ptrdiff_t off = it - mData;
+		if (it < mData + mSize - 1) std::memcpy(mData + off, mData + mSize - 1, sizeof(T));
+		mSize--;
+		return mData + off;
+	}
+
+	T* insert(const T* it, const T& v) {
+		assert(it >= mData && it <= mData + mSize);
+		const ptrdiff_t off = it - mData;
+		if (mSize == mCapacity) reserve(grow_capacity(mSize + 1));
+		if (off < (int)mSize) std::memmove(mData + off + 1, mData + off, ((size_t)mSize - (size_t)off) * sizeof(T));
+		std::memcpy(&mData[off], &v, sizeof(v));
+		mSize++;
+		return mData + off;
+	}
+
+	bool contains(const T& v) const {
+		const T* data = mData;
+		const T* dataEnd = mData + mSize;
+		while (data < dataEnd) {
+			if (*data++ == v) return true;
+		}
+		return false;
+	}
+
+	T* find(const T& v) {
+		T* data = mData;
+		const T* dataEnd = mData + mSize;
+		while (data < dataEnd)
+			if (*data == v)
+				break;
+			else
+				++data;
+		return data;
+	}
+
+	const T* find(const T& v) const {
+		const T* data = mData;
+		const T* dataEnd = mData + mSize;
+		while (data < dataEnd)
+			if (*data == v)
+				break;
+			else
+				++data;
+		return data;
+	}
+
+	bool find_erase(const T& v) {
+		const T* it = find(v);
+		if (it < mData + mSize) {
+			erase(it);
+			return true;
+		}
+		return false;
+	}
+
+	bool find_erase_unsorted(const T& v) {
+		const T* it = find(v);
+		if (it < mData + mSize) {
+			erase_unsorted(it);
+			return true;
+		}
+		return false;
+	}
+
+	int index_from_ptr(const T* it) const {
+		assert(it >= mData && it < mData + mSize);
+		const ptrdiff_t off = it - mData;
+		return (int)off;
+	}
+
+	// Custom utility functions
+
+	std::span<T> as_span() { return { mData, (size_t)mSize }; }
+	std::span<uint8_t> as_data_span() { return { (uint8_t*)mData, (size_t)mSize * sizeof(T) }; }
+	std::span<const T> as_span() const { return { mData, (size_t)mSize }; }
+	std::span<const uint8_t> as_data_span() const { return { (uint8_t*)mData, (size_t)mSize * sizeof(T) }; }
+};
diff --git a/source-common/RcPtr.hpp b/source-common/RcPtr.hpp
new file mode 100644
index 0000000..130b2b2
--- /dev/null
+++ b/source-common/RcPtr.hpp
@@ -0,0 +1,120 @@
+#pragma once
+
+#include "Macros.hpp"
+#include "TypeTraits.hpp"
+
+#include <cstddef>
+#include <cstdint>
+#include <optional>
+#include <type_traits>
+
+class RefCounted {
+public:
+	// DO NOT MODIFY this field, unless explicitly documented the use
+	uint32_t refCount = 0;
+	uint32_t weakCount = 0; // TODO implement
+};
+
+template <class T, class TDeleter = DefaultDeleter<T>>
+class RcPtr : TDeleter {
+private:
+	static_assert(std::is_base_of_v<RefCounted, T>);
+	T* mPtr;
+
+public:
+	RcPtr()
+		: mPtr{ nullptr } {
+	}
+
+	explicit RcPtr(T* ptr)
+		: mPtr{ ptr } {
+		if (ptr) {
+			++ptr->RefCounted::refCount;
+		}
+	}
+
+	~RcPtr() {
+		CleanUp();
+	}
+
+	void Attach(T* ptr) {
+		CleanUp();
+		mPtr = ptr;
+		if (ptr) {
+			++ptr->RefCounted::refCount;
+		}
+	}
+
+	void Detatch() {
+		CleanUp();
+		mPtr = nullptr;
+	}
+
+	RcPtr(const RcPtr& that)
+		: mPtr{ that.mPtr } {
+		if (mPtr) {
+			++mPtr->RefCounted::refCount;
+		}
+	}
+
+	RcPtr& operator=(const RcPtr& that) {
+		CleanUp();
+		mPtr = that.mPtr;
+		if (mPtr) {
+			++mPtr->RefCounted::refCount;
+		}
+		return *this;
+	}
+
+	RcPtr(RcPtr&& that)
+		: mPtr{ that.mPtr } {
+		that.mPtr = nullptr;
+	}
+
+	RcPtr& operator=(RcPtr&& that) {
+		CleanUp();
+		mPtr = that.mPtr;
+		that.mPtr = nullptr;
+		return *this;
+	}
+
+	template <class TBase>
+	requires std::is_base_of_v<TBase, T>
+	operator RcPtr<TBase>() const {
+		return RcPtr<TBase>(mPtr);
+	}
+
+	bool operator==(std::nullptr_t ptr) const {
+		return mPtr == nullptr;
+	}
+
+	bool operator==(const T* ptr) const {
+		return mPtr == ptr;
+	}
+
+	bool operator==(T* ptr) const {
+		return mPtr == ptr;
+	}
+
+	template <class TThat>
+	bool operator==(const RcPtr<TThat>& ptr) const {
+		return mPtr == ptr.Get();
+	}
+
+	T* Get() const {
+		return mPtr;
+	}
+
+	T& operator*() const { return *mPtr; }
+	T* operator->() const { return mPtr; }
+
+private:
+	void CleanUp() {
+		if (mPtr) {
+			--mPtr->RefCounted::refCount;
+			if (mPtr->RefCounted::refCount == 0) {
+				TDeleter::operator()(mPtr);
+			}
+		}
+	}
+};
diff --git a/source-common/Rect.hpp b/source-common/Rect.hpp
new file mode 100644
index 0000000..89d9b01
--- /dev/null
+++ b/source-common/Rect.hpp
@@ -0,0 +1,164 @@
+#pragma once
+
+#include <glm/glm.hpp>
+
+/// Rect is a rectangle representation based on a point and a dimensions, in television coordinate space
+/// (x increases from left to right, y increases from top to bottom).
+template <class T>
+class Rect {
+public:
+	using ScalarType = T;
+	using VectorType = glm::vec<2, T>;
+
+public:
+	T x;
+	T y;
+	T width;
+	T height;
+
+public:
+	Rect()
+		: x{ 0 }, y{ 0 }, width{ 0 }, height{ 0 } {
+	}
+
+	Rect(T x, T y, T width, T height)
+		: x{ x }, y{ y }, width{ width }, height{ height } {
+	}
+
+	Rect(VectorType pos, VectorType size)
+		: x{ pos.x }
+		, y{ pos.y }
+		, width{ size.x }
+		, height{ size.y } {
+	}
+
+	T x0() const { return x; }
+	T y0() const { return y; }
+	T x1() const { return x + width; }
+	T y1() const { return y + height; }
+
+	VectorType TopLeft() const {
+		return VectorType{ x, y };
+	}
+
+	VectorType TopRight() const {
+		return VectorType{ x + width, y };
+	}
+
+	VectorType BottomLeft() const {
+		return VectorType{ x, y + height };
+	}
+
+	VectorType BottomRight() const {
+		return VectorType{ x + width, y + height };
+	}
+
+	VectorType Center() const {
+		return TopLeft() + VectorType{ width / 2, height / 2 };
+	}
+
+	VectorType Dimensions() const {
+		return VectorType{ width, height };
+	}
+
+	VectorType Extents() const {
+		return VectorType{ width / 2, height / 2 };
+	}
+
+	/// Assumes `bySize * 2` is smaller than both `width` and `height` (does not produce a negative-dimension rectangle).
+	Rect Shrink(T bySize) const {
+		T two = bySize * 2;
+		return Rect{ x + bySize, y + bySize, width - two, height - two };
+	}
+
+	Rect Shrink(T left, T top, T right, T bottom) const {
+		return Rect{
+			x + left,
+			y + top,
+			width - left - right,
+			height - top - bottom,
+		};
+	}
+
+	Rect Expand(T bySize) const {
+		T two = bySize * 2;
+		return Rect{ x - bySize, y - bySize, width + two, height + two };
+	}
+
+	Rect Expand(T left, T top, T right, T bottom) const {
+		return Rect{
+			x - left,
+			y - top,
+			width + left + right,
+			height + top + bottom,
+		};
+	}
+
+	bool Contains(VectorType point) const {
+		return point.x >= x &&
+			point.y >= y &&
+			point.x < x + width &&
+			point.y < y + height;
+	}
+
+	bool Intersects(const Rect& that) const {
+		bool xBetween = x > that.x0() && x < that.x1();
+		bool yBetween = y > that.y0() && y < that.y1();
+		return xBetween && yBetween;
+	}
+
+	// Write min()/max() tenary by hand so that we don't have to include <algorithm>
+	// This file is practically going to be included in every file in this project
+
+	static Rect Intersection(const Rect& a, const Rect& b) {
+		auto x0 = a.x0() > b.x0() ? a.x0() : b.x0(); // Max
+		auto y0 = a.y0() > b.y0() ? a.y0() : b.y0(); // Max
+		auto x1 = a.x1() < b.x1() ? a.x1() : b.x1(); // Min
+		auto y1 = a.y1() < b.y1() ? a.y1() : b.y1(); // Min
+		auto width = x1 - x0;
+		auto height = y1 - x0;
+		return Rect{ x0, y0, width, height };
+	}
+
+	static Rect Union(const Rect& a, const Rect& b) {
+		auto x0 = a.x0() < b.x0() ? a.x0() : b.x0(); // Min
+		auto y0 = a.y0() < b.y0() ? a.y0() : b.y0(); // Min
+		auto x1 = a.x1() > b.x1() ? a.x1() : b.x1(); // Max
+		auto y1 = a.y1() > b.y1() ? a.y1() : b.y1(); // Max
+		auto width = x1 - x0;
+		auto height = y1 - x0;
+		return Rect{ x0, y0, width, height };
+	}
+
+	friend bool operator==(const Rect<T>&, const Rect<T>&) = default;
+
+	Rect operator+(glm::vec<2, T> offset) const {
+		return { x + offset.x, y + offset.y, width, height };
+	}
+
+	Rect operator-(glm::vec<2, T> offset) const {
+		return { x - offset.x, y - offset.y, width, height };
+	}
+
+	Rect& operator+=(glm::vec<2, T> offset) {
+		x += offset.x;
+		y += offset.y;
+		return *this;
+	}
+
+	Rect& operator-=(glm::vec<2, T> offset) {
+		x -= offset.x;
+		y -= offset.y;
+		return *this;
+	}
+
+	template <class TTarget>
+	Rect<TTarget> Cast() const {
+		return {
+			static_cast<TTarget>(x),
+			static_cast<TTarget>(y),
+			static_cast<TTarget>(width),
+			static_cast<TTarget>(height),
+		};
+	}
+};
diff --git a/source-common/SmallVector.cpp b/source-common/SmallVector.cpp
new file mode 100644
index 0000000..c38e8a7
--- /dev/null
+++ b/source-common/SmallVector.cpp
@@ -0,0 +1,145 @@
+// Obtained from https://github.com/llvm/llvm-project/blob/main/llvm/lib/Support/SmallVector.cpp
+// commit 4b82bb6d82f65f98f23d0e4c2cd5297dc162864c
+// adapted in code style and utilities to fix this project
+
+//===- llvm/ADT/SmallVector.cpp - 'Normally small' vectors ----------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the SmallVector class.
+//
+//===----------------------------------------------------------------------===//
+
+#include "SmallVector.hpp"
+
+#include <cstdlib>
+#include <stdexcept>
+#include <string>
+
+// Check that no bytes are wasted and everything is well-aligned.
+namespace {
+// These structures may cause binary compat warnings on AIX. Suppress the
+// warning since we are only using these types for the static assertions below.
+#if defined(_AIX)
+#	pragma GCC diagnostic push
+#	pragma GCC diagnostic ignored "-Waix-compat"
+#endif
+struct Struct16B {
+	alignas(16) void* X;
+};
+struct Struct32B {
+	alignas(32) void* X;
+};
+#if defined(_AIX)
+#	pragma GCC diagnostic pop
+#endif
+} // namespace
+static_assert(sizeof(SmallVector<void*, 0>) ==
+		sizeof(unsigned) * 2 + sizeof(void*),
+	"wasted space in SmallVector size 0");
+static_assert(alignof(SmallVector<Struct16B, 0>) >= alignof(Struct16B),
+	"wrong alignment for 16-byte aligned T");
+static_assert(alignof(SmallVector<Struct32B, 0>) >= alignof(Struct32B),
+	"wrong alignment for 32-byte aligned T");
+static_assert(sizeof(SmallVector<Struct16B, 0>) >= alignof(Struct16B),
+	"missing padding for 16-byte aligned T");
+static_assert(sizeof(SmallVector<Struct32B, 0>) >= alignof(Struct32B),
+	"missing padding for 32-byte aligned T");
+static_assert(sizeof(SmallVector<void*, 1>) ==
+		sizeof(unsigned) * 2 + sizeof(void*) * 2,
+	"wasted space in SmallVector size 1");
+
+static_assert(sizeof(SmallVector<char, 0>) ==
+		sizeof(void*) * 2 + sizeof(void*),
+	"1 byte elements have word-sized type for size and capacity");
+
+/// Report that MinSize doesn't fit into this vector's size type. Throws
+/// std::length_error or calls report_fatal_error.
+[[noreturn]] static void report_size_overflow(size_t MinSize, size_t MaxSize);
+static void report_size_overflow(size_t MinSize, size_t MaxSize) {
+	std::string Reason = "SmallVector unable to grow. Requested capacity (" +
+		std::to_string(MinSize) +
+		") is larger than maximum value for size type (" +
+		std::to_string(MaxSize) + ")";
+	throw std::length_error(Reason);
+}
+
+/// Report that this vector is already at maximum capacity. Throws
+/// std::length_error or calls report_fatal_error.
+[[noreturn]] static void report_at_maximum_capacity(size_t MaxSize);
+static void report_at_maximum_capacity(size_t MaxSize) {
+	std::string Reason =
+		"SmallVector capacity unable to grow. Already at maximum size " +
+		std::to_string(MaxSize);
+	throw std::length_error(Reason);
+}
+
+// Note: Moving this function into the header may cause performance regression.
+template <class Size_T>
+static size_t getNewCapacity(size_t MinSize, size_t TSize, size_t OldCapacity) {
+	constexpr size_t MaxSize = std::numeric_limits<Size_T>::max();
+
+	// Ensure we can fit the new capacity.
+	// This is only going to be applicable when the capacity is 32 bit.
+	if (MinSize > MaxSize)
+		report_size_overflow(MinSize, MaxSize);
+
+	// Ensure we can meet the guarantee of space for at least one more element.
+	// The above check alone will not catch the case where grow is called with a
+	// default MinSize of 0, but the current capacity cannot be increased.
+	// This is only going to be applicable when the capacity is 32 bit.
+	if (OldCapacity == MaxSize)
+		report_at_maximum_capacity(MaxSize);
+
+	// In theory 2*capacity can overflow if the capacity is 64 bit, but the
+	// original capacity would never be large enough for this to be a problem.
+	size_t NewCapacity = 2 * OldCapacity + 1; // Always grow.
+	return std::min(std::max(NewCapacity, MinSize), MaxSize);
+}
+
+// Note: Moving this function into the header may cause performance regression.
+template <class Size_T>
+void* SmallVectorBase<Size_T>::mallocForGrow(size_t MinSize, size_t TSize, size_t& NewCapacity) {
+	NewCapacity = getNewCapacity<Size_T>(MinSize, TSize, this->capacity());
+	return malloc(NewCapacity * TSize);
+}
+
+// Note: Moving this function into the header may cause performance regression.
+template <class Size_T>
+void SmallVectorBase<Size_T>::grow_pod(void* FirstEl, size_t MinSize, size_t TSize) {
+	size_t NewCapacity = getNewCapacity<Size_T>(MinSize, TSize, this->capacity());
+	void* NewElts;
+	if (BeginX == FirstEl) {
+		NewElts = malloc(NewCapacity * TSize);
+
+		// Copy the elements over.  No need to run dtors on PODs.
+		memcpy(NewElts, this->BeginX, size() * TSize);
+	} else {
+		// If this wasn't grown from the inline copy, grow the allocated space.
+		NewElts = realloc(this->BeginX, NewCapacity * TSize);
+	}
+
+	this->BeginX = NewElts;
+	this->Capacity = NewCapacity;
+}
+
+template class SmallVectorBase<uint32_t>;
+
+// Disable the uint64_t instantiation for 32-bit builds.
+// Both uint32_t and uint64_t instantiations are needed for 64-bit builds.
+// This instantiation will never be used in 32-bit builds, and will cause
+// warnings when sizeof(Size_T) > sizeof(size_t).
+#if SIZE_MAX > UINT32_MAX
+template class SmallVectorBase<uint64_t>;
+
+// Assertions to ensure this #if stays in sync with SmallVectorSizeType.
+static_assert(sizeof(SmallVectorSizeType<char>) == sizeof(uint64_t),
+	"Expected SmallVectorBase<uint64_t> variant to be in use.");
+#else
+static_assert(sizeof(SmallVectorSizeType<char>) == sizeof(uint32_t),
+	"Expected SmallVectorBase<uint32_t> variant to be in use.");
+#endif
diff --git a/source-common/SmallVector.hpp b/source-common/SmallVector.hpp
new file mode 100644
index 0000000..e33a25d
--- /dev/null
+++ b/source-common/SmallVector.hpp
@@ -0,0 +1,1332 @@
+// Obtained from https://github.com/llvm/llvm-project/blob/main/llvm/include/llvm/ADT/SmallVector.h
+// commit 4b82bb6d82f65f98f23d0e4c2cd5297dc162864c
+// adapted in code style and utilities to fix this project
+
+//===- llvm/ADT/SmallVector.h - 'Normally small' vectors --------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// This file defines the SmallVector class.
+///
+//===----------------------------------------------------------------------===//
+
+#pragma once
+
+#include <algorithm>
+#include <cassert>
+#include <cstddef>
+#include <cstdlib>
+#include <cstring>
+#include <functional>
+#include <initializer_list>
+#include <iterator>
+#include <limits>
+#include <memory>
+#include <new>
+#include <type_traits>
+#include <utility>
+
+#ifdef _MSC_VER
+#	pragma warning(push)
+#	pragma warning(disable : 4267) // The compiler detected a conversion from size_t to a smaller type.
+#endif
+
+#if __has_builtin(__builtin_expect) || defined(__GNUC__)
+#	define LLVM_LIKELY(EXPR) __builtin_expect((bool)(EXPR), true)
+#	define LLVM_UNLIKELY(EXPR) __builtin_expect((bool)(EXPR), false)
+#else
+#	define LLVM_LIKELY(EXPR) (EXPR)
+#	define LLVM_UNLIKELY(EXPR) (EXPR)
+#endif
+
+template <typename IteratorT>
+class iterator_range;
+
+/// This is all the stuff common to all SmallVectors.
+///
+/// The template parameter specifies the type which should be used to hold the
+/// Size and Capacity of the SmallVector, so it can be adjusted.
+/// Using 32 bit size is desirable to shrink the size of the SmallVector.
+/// Using 64 bit size is desirable for cases like SmallVector<char>, where a
+/// 32 bit size would limit the vector to ~4GB. SmallVectors are used for
+/// buffering bitcode output - which can exceed 4GB.
+template <class Size_T>
+class SmallVectorBase {
+protected:
+	void* BeginX;
+	Size_T Size = 0, Capacity;
+
+	/// The maximum value of the Size_T used.
+	static constexpr size_t SizeTypeMax() {
+		return std::numeric_limits<Size_T>::max();
+	}
+
+	SmallVectorBase() = delete;
+	SmallVectorBase(void* FirstEl, size_t TotalCapacity)
+		: BeginX(FirstEl), Capacity(TotalCapacity) {}
+
+	/// This is a helper for \a grow() that's out of line to reduce code
+	/// duplication.  This function will report a fatal error if it can't grow at
+	/// least to \p MinSize.
+	void* mallocForGrow(size_t MinSize, size_t TSize, size_t& NewCapacity);
+
+	/// This is an implementation of the grow() method which only works
+	/// on POD-like data types and is out of line to reduce code duplication.
+	/// This function will report a fatal error if it cannot increase capacity.
+	void grow_pod(void* FirstEl, size_t MinSize, size_t TSize);
+
+public:
+	size_t size() const { return Size; }
+	size_t capacity() const { return Capacity; }
+
+	[[nodiscard]] bool empty() const { return !Size; }
+
+protected:
+	/// Set the array size to \p N, which the current array must have enough
+	/// capacity for.
+	///
+	/// This does not construct or destroy any elements in the vector.
+	void set_size(size_t N) {
+		assert(N <= capacity());
+		Size = N;
+	}
+};
+
+template <class T>
+using SmallVectorSizeType =
+	typename std::conditional<sizeof(T) < 4 && sizeof(void*) >= 8, uint64_t, uint32_t>::type;
+
+/// Figure out the offset of the first element.
+template <class T, typename = void>
+struct SmallVectorAlignmentAndSize {
+	alignas(SmallVectorBase<SmallVectorSizeType<T>>) char Base[sizeof(
+		SmallVectorBase<SmallVectorSizeType<T>>)];
+	alignas(T) char FirstEl[sizeof(T)];
+};
+
+/// This is the part of SmallVectorTemplateBase which does not depend on whether
+/// the type T is a POD. The extra dummy template argument is used by ArrayRef
+/// to avoid unnecessarily requiring T to be complete.
+template <typename T, typename = void>
+class SmallVectorTemplateCommon
+	: public SmallVectorBase<SmallVectorSizeType<T>> {
+	using Base = SmallVectorBase<SmallVectorSizeType<T>>;
+
+	/// Find the address of the first element.  For this pointer math to be valid
+	/// with small-size of 0 for T with lots of alignment, it's important that
+	/// SmallVectorStorage is properly-aligned even for small-size of 0.
+	void* getFirstEl() const {
+		return const_cast<void*>(reinterpret_cast<const void*>(
+			reinterpret_cast<const char*>(this) +
+			offsetof(SmallVectorAlignmentAndSize<T>, FirstEl)));
+	}
+	// Space after 'FirstEl' is clobbered, do not add any instance vars after it.
+
+protected:
+	SmallVectorTemplateCommon(size_t Size)
+		: Base(getFirstEl(), Size) {}
+
+	void grow_pod(size_t MinSize, size_t TSize) {
+		Base::grow_pod(getFirstEl(), MinSize, TSize);
+	}
+
+	/// Return true if this is a smallvector which has not had dynamic
+	/// memory allocated for it.
+	bool isSmall() const { return this->BeginX == getFirstEl(); }
+
+	/// Put this vector in a state of being small.
+	void resetToSmall() {
+		this->BeginX = getFirstEl();
+		this->Size = this->Capacity = 0; // FIXME: Setting Capacity to 0 is suspect.
+	}
+
+	/// Return true if V is an internal reference to the given range.
+	bool isReferenceToRange(const void* V, const void* First, const void* Last) const {
+		// Use std::less to avoid UB.
+		std::less<> LessThan;
+		return !LessThan(V, First) && LessThan(V, Last);
+	}
+
+	/// Return true if V is an internal reference to this vector.
+	bool isReferenceToStorage(const void* V) const {
+		return isReferenceToRange(V, this->begin(), this->end());
+	}
+
+	/// Return true if First and Last form a valid (possibly empty) range in this
+	/// vector's storage.
+	bool isRangeInStorage(const void* First, const void* Last) const {
+		// Use std::less to avoid UB.
+		std::less<> LessThan;
+		return !LessThan(First, this->begin()) && !LessThan(Last, First) &&
+			!LessThan(this->end(), Last);
+	}
+
+	/// Return true unless Elt will be invalidated by resizing the vector to
+	/// NewSize.
+	bool isSafeToReferenceAfterResize(const void* Elt, size_t NewSize) {
+		// Past the end.
+		if (LLVM_LIKELY(!isReferenceToStorage(Elt)))
+			return true;
+
+		// Return false if Elt will be destroyed by shrinking.
+		if (NewSize <= this->size())
+			return Elt < this->begin() + NewSize;
+
+		// Return false if we need to grow.
+		return NewSize <= this->capacity();
+	}
+
+	/// Check whether Elt will be invalidated by resizing the vector to NewSize.
+	void assertSafeToReferenceAfterResize(const void* Elt, size_t NewSize) {
+		assert(isSafeToReferenceAfterResize(Elt, NewSize) &&
+			"Attempting to reference an element of the vector in an operation "
+			"that invalidates it");
+	}
+
+	/// Check whether Elt will be invalidated by increasing the size of the
+	/// vector by N.
+	void assertSafeToAdd(const void* Elt, size_t N = 1) {
+		this->assertSafeToReferenceAfterResize(Elt, this->size() + N);
+	}
+
+	/// Check whether any part of the range will be invalidated by clearing.
+	void assertSafeToReferenceAfterClear(const T* From, const T* To) {
+		if (From == To)
+			return;
+		this->assertSafeToReferenceAfterResize(From, 0);
+		this->assertSafeToReferenceAfterResize(To - 1, 0);
+	}
+	template <
+		class ItTy,
+		std::enable_if_t<!std::is_same<std::remove_const_t<ItTy>, T*>::value,
+			bool> = false>
+	void assertSafeToReferenceAfterClear(ItTy, ItTy) {}
+
+	/// Check whether any part of the range will be invalidated by growing.
+	void assertSafeToAddRange(const T* From, const T* To) {
+		if (From == To)
+			return;
+		this->assertSafeToAdd(From, To - From);
+		this->assertSafeToAdd(To - 1, To - From);
+	}
+	template <
+		class ItTy,
+		std::enable_if_t<!std::is_same<std::remove_const_t<ItTy>, T*>::value,
+			bool> = false>
+	void assertSafeToAddRange(ItTy, ItTy) {}
+
+	/// Reserve enough space to add one element, and return the updated element
+	/// pointer in case it was a reference to the storage.
+	template <class U>
+	static const T* reserveForParamAndGetAddressImpl(U* This, const T& Elt, size_t N) {
+		size_t NewSize = This->size() + N;
+		if (LLVM_LIKELY(NewSize <= This->capacity()))
+			return &Elt;
+
+		bool ReferencesStorage = false;
+		int64_t Index = -1;
+		if (!U::TakesParamByValue) {
+			if (LLVM_UNLIKELY(This->isReferenceToStorage(&Elt))) {
+				ReferencesStorage = true;
+				Index = &Elt - This->begin();
+			}
+		}
+		This->grow(NewSize);
+		return ReferencesStorage ? This->begin() + Index : &Elt;
+	}
+
+public:
+	using size_type = size_t;
+	using difference_type = ptrdiff_t;
+	using value_type = T;
+	using iterator = T*;
+	using const_iterator = const T*;
+
+	using const_reverse_iterator = std::reverse_iterator<const_iterator>;
+	using reverse_iterator = std::reverse_iterator<iterator>;
+
+	using reference = T&;
+	using const_reference = const T&;
+	using pointer = T*;
+	using const_pointer = const T*;
+
+	using Base::capacity;
+	using Base::empty;
+	using Base::size;
+
+	// forward iterator creation methods.
+	iterator begin() { return (iterator)this->BeginX; }
+	const_iterator begin() const { return (const_iterator)this->BeginX; }
+	iterator end() { return begin() + size(); }
+	const_iterator end() const { return begin() + size(); }
+
+	// reverse iterator creation methods.
+	reverse_iterator rbegin() { return reverse_iterator(end()); }
+	const_reverse_iterator rbegin() const { return const_reverse_iterator(end()); }
+	reverse_iterator rend() { return reverse_iterator(begin()); }
+	const_reverse_iterator rend() const { return const_reverse_iterator(begin()); }
+
+	size_type size_in_bytes() const { return size() * sizeof(T); }
+	size_type max_size() const {
+		return std::min(this->SizeTypeMax(), size_type(-1) / sizeof(T));
+	}
+
+	size_t capacity_in_bytes() const { return capacity() * sizeof(T); }
+
+	/// Return a pointer to the vector's buffer, even if empty().
+	pointer data() { return pointer(begin()); }
+	/// Return a pointer to the vector's buffer, even if empty().
+	const_pointer data() const { return const_pointer(begin()); }
+
+	reference operator[](size_type idx) {
+		assert(idx < size());
+		return begin()[idx];
+	}
+	const_reference operator[](size_type idx) const {
+		assert(idx < size());
+		return begin()[idx];
+	}
+
+	reference front() {
+		assert(!empty());
+		return begin()[0];
+	}
+	const_reference front() const {
+		assert(!empty());
+		return begin()[0];
+	}
+
+	reference back() {
+		assert(!empty());
+		return end()[-1];
+	}
+	const_reference back() const {
+		assert(!empty());
+		return end()[-1];
+	}
+};
+
+/// SmallVectorTemplateBase<TriviallyCopyable = false> - This is where we put
+/// method implementations that are designed to work with non-trivial T's.
+///
+/// We approximate is_trivially_copyable with trivial move/copy construction and
+/// trivial destruction. While the standard doesn't specify that you're allowed
+/// copy these types with memcpy, there is no way for the type to observe this.
+/// This catches the important case of std::pair<POD, POD>, which is not
+/// trivially assignable.
+template <typename T, bool = (std::is_trivially_copy_constructible<T>::value) && (std::is_trivially_move_constructible<T>::value) && std::is_trivially_destructible<T>::value>
+class SmallVectorTemplateBase : public SmallVectorTemplateCommon<T> {
+	friend class SmallVectorTemplateCommon<T>;
+
+protected:
+	static constexpr bool TakesParamByValue = false;
+	using ValueParamT = const T&;
+
+	SmallVectorTemplateBase(size_t Size)
+		: SmallVectorTemplateCommon<T>(Size) {}
+
+	static void destroy_range(T* S, T* E) {
+		while (S != E) {
+			--E;
+			E->~T();
+		}
+	}
+
+	/// Move the range [I, E) into the uninitialized memory starting with "Dest",
+	/// constructing elements as needed.
+	template <typename It1, typename It2>
+	static void uninitialized_move(It1 I, It1 E, It2 Dest) {
+		std::uninitialized_copy(std::make_move_iterator(I),
+			std::make_move_iterator(E),
+			Dest);
+	}
+
+	/// Copy the range [I, E) onto the uninitialized memory starting with "Dest",
+	/// constructing elements as needed.
+	template <typename It1, typename It2>
+	static void uninitialized_copy(It1 I, It1 E, It2 Dest) {
+		std::uninitialized_copy(I, E, Dest);
+	}
+
+	/// Grow the allocated memory (without initializing new elements), doubling
+	/// the size of the allocated memory. Guarantees space for at least one more
+	/// element, or MinSize more elements if specified.
+	void grow(size_t MinSize = 0);
+
+	/// Create a new allocation big enough for \p MinSize and pass back its size
+	/// in \p NewCapacity. This is the first section of \a grow().
+	T* mallocForGrow(size_t MinSize, size_t& NewCapacity) {
+		return static_cast<T*>(
+			SmallVectorBase<SmallVectorSizeType<T>>::mallocForGrow(
+				MinSize, sizeof(T), NewCapacity));
+	}
+
+	/// Move existing elements over to the new allocation \p NewElts, the middle
+	/// section of \a grow().
+	void moveElementsForGrow(T* NewElts);
+
+	/// Transfer ownership of the allocation, finishing up \a grow().
+	void takeAllocationForGrow(T* NewElts, size_t NewCapacity);
+
+	/// Reserve enough space to add one element, and return the updated element
+	/// pointer in case it was a reference to the storage.
+	const T* reserveForParamAndGetAddress(const T& Elt, size_t N = 1) {
+		return this->reserveForParamAndGetAddressImpl(this, Elt, N);
+	}
+
+	/// Reserve enough space to add one element, and return the updated element
+	/// pointer in case it was a reference to the storage.
+	T* reserveForParamAndGetAddress(T& Elt, size_t N = 1) {
+		return const_cast<T*>(
+			this->reserveForParamAndGetAddressImpl(this, Elt, N));
+	}
+
+	static T&& forward_value_param(T&& V) { return std::move(V); }
+	static const T& forward_value_param(const T& V) { return V; }
+
+	void growAndAssign(size_t NumElts, const T& Elt) {
+		// Grow manually in case Elt is an internal reference.
+		size_t NewCapacity;
+		T* NewElts = mallocForGrow(NumElts, NewCapacity);
+		std::uninitialized_fill_n(NewElts, NumElts, Elt);
+		this->destroy_range(this->begin(), this->end());
+		takeAllocationForGrow(NewElts, NewCapacity);
+		this->set_size(NumElts);
+	}
+
+	template <typename... ArgTypes>
+	T& growAndEmplaceBack(ArgTypes&&... Args) {
+		// Grow manually in case one of Args is an internal reference.
+		size_t NewCapacity;
+		T* NewElts = mallocForGrow(0, NewCapacity);
+		::new ((void*)(NewElts + this->size())) T(std::forward<ArgTypes>(Args)...);
+		moveElementsForGrow(NewElts);
+		takeAllocationForGrow(NewElts, NewCapacity);
+		this->set_size(this->size() + 1);
+		return this->back();
+	}
+
+public:
+	void push_back(const T& Elt) {
+		const T* EltPtr = reserveForParamAndGetAddress(Elt);
+		::new ((void*)this->end()) T(*EltPtr);
+		this->set_size(this->size() + 1);
+	}
+
+	void push_back(T&& Elt) {
+		T* EltPtr = reserveForParamAndGetAddress(Elt);
+		::new ((void*)this->end()) T(::std::move(*EltPtr));
+		this->set_size(this->size() + 1);
+	}
+
+	void pop_back() {
+		this->set_size(this->size() - 1);
+		this->end()->~T();
+	}
+};
+
+// Define this out-of-line to dissuade the C++ compiler from inlining it.
+template <typename T, bool TriviallyCopyable>
+void SmallVectorTemplateBase<T, TriviallyCopyable>::grow(size_t MinSize) {
+	size_t NewCapacity;
+	T* NewElts = mallocForGrow(MinSize, NewCapacity);
+	moveElementsForGrow(NewElts);
+	takeAllocationForGrow(NewElts, NewCapacity);
+}
+
+// Define this out-of-line to dissuade the C++ compiler from inlining it.
+template <typename T, bool TriviallyCopyable>
+void SmallVectorTemplateBase<T, TriviallyCopyable>::moveElementsForGrow(
+	T* NewElts) {
+	// Move the elements over.
+	this->uninitialized_move(this->begin(), this->end(), NewElts);
+
+	// Destroy the original elements.
+	destroy_range(this->begin(), this->end());
+}
+
+// Define this out-of-line to dissuade the C++ compiler from inlining it.
+template <typename T, bool TriviallyCopyable>
+void SmallVectorTemplateBase<T, TriviallyCopyable>::takeAllocationForGrow(
+	T* NewElts, size_t NewCapacity) {
+	// If this wasn't grown from the inline copy, deallocate the old space.
+	if (!this->isSmall())
+		free(this->begin());
+
+	this->BeginX = NewElts;
+	this->Capacity = NewCapacity;
+}
+
+/// SmallVectorTemplateBase<TriviallyCopyable = true> - This is where we put
+/// method implementations that are designed to work with trivially copyable
+/// T's. This allows using memcpy in place of copy/move construction and
+/// skipping destruction.
+template <typename T>
+class SmallVectorTemplateBase<T, true> : public SmallVectorTemplateCommon<T> {
+	friend class SmallVectorTemplateCommon<T>;
+
+protected:
+	/// True if it's cheap enough to take parameters by value. Doing so avoids
+	/// overhead related to mitigations for reference invalidation.
+	static constexpr bool TakesParamByValue = sizeof(T) <= 2 * sizeof(void*);
+
+	/// Either const T& or T, depending on whether it's cheap enough to take
+	/// parameters by value.
+	using ValueParamT =
+		typename std::conditional<TakesParamByValue, T, const T&>::type;
+
+	SmallVectorTemplateBase(size_t Size)
+		: SmallVectorTemplateCommon<T>(Size) {}
+
+	// No need to do a destroy loop for POD's.
+	static void destroy_range(T*, T*) {}
+
+	/// Move the range [I, E) onto the uninitialized memory
+	/// starting with "Dest", constructing elements into it as needed.
+	template <typename It1, typename It2>
+	static void uninitialized_move(It1 I, It1 E, It2 Dest) {
+		// Just do a copy.
+		uninitialized_copy(I, E, Dest);
+	}
+
+	/// Copy the range [I, E) onto the uninitialized memory
+	/// starting with "Dest", constructing elements into it as needed.
+	template <typename It1, typename It2>
+	static void uninitialized_copy(It1 I, It1 E, It2 Dest) {
+		// Arbitrary iterator types; just use the basic implementation.
+		std::uninitialized_copy(I, E, Dest);
+	}
+
+	/// Copy the range [I, E) onto the uninitialized memory
+	/// starting with "Dest", constructing elements into it as needed.
+	template <typename T1, typename T2>
+	static void uninitialized_copy(
+		T1* I, T1* E, T2* Dest, std::enable_if_t<std::is_same<typename std::remove_const<T1>::type, T2>::value>* = nullptr) {
+		// Use memcpy for PODs iterated by pointers (which includes SmallVector
+		// iterators): std::uninitialized_copy optimizes to memmove, but we can
+		// use memcpy here. Note that I and E are iterators and thus might be
+		// invalid for memcpy if they are equal.
+		if (I != E)
+			memcpy(reinterpret_cast<void*>(Dest), I, (E - I) * sizeof(T));
+	}
+
+	/// Double the size of the allocated memory, guaranteeing space for at
+	/// least one more element or MinSize if specified.
+	void grow(size_t MinSize = 0) { this->grow_pod(MinSize, sizeof(T)); }
+
+	/// Reserve enough space to add one element, and return the updated element
+	/// pointer in case it was a reference to the storage.
+	const T* reserveForParamAndGetAddress(const T& Elt, size_t N = 1) {
+		return this->reserveForParamAndGetAddressImpl(this, Elt, N);
+	}
+
+	/// Reserve enough space to add one element, and return the updated element
+	/// pointer in case it was a reference to the storage.
+	T* reserveForParamAndGetAddress(T& Elt, size_t N = 1) {
+		return const_cast<T*>(
+			this->reserveForParamAndGetAddressImpl(this, Elt, N));
+	}
+
+	/// Copy \p V or return a reference, depending on \a ValueParamT.
+	static ValueParamT forward_value_param(ValueParamT V) { return V; }
+
+	void growAndAssign(size_t NumElts, T Elt) {
+		// Elt has been copied in case it's an internal reference, side-stepping
+		// reference invalidation problems without losing the realloc optimization.
+		this->set_size(0);
+		this->grow(NumElts);
+		std::uninitialized_fill_n(this->begin(), NumElts, Elt);
+		this->set_size(NumElts);
+	}
+
+	template <typename... ArgTypes>
+	T& growAndEmplaceBack(ArgTypes&&... Args) {
+		// Use push_back with a copy in case Args has an internal reference,
+		// side-stepping reference invalidation problems without losing the realloc
+		// optimization.
+		push_back(T(std::forward<ArgTypes>(Args)...));
+		return this->back();
+	}
+
+public:
+	void push_back(ValueParamT Elt) {
+		const T* EltPtr = reserveForParamAndGetAddress(Elt);
+		memcpy(reinterpret_cast<void*>(this->end()), EltPtr, sizeof(T));
+		this->set_size(this->size() + 1);
+	}
+
+	void pop_back() { this->set_size(this->size() - 1); }
+};
+
+/// This class consists of common code factored out of the SmallVector class to
+/// reduce code duplication based on the SmallVector 'N' template parameter.
+template <typename T>
+class SmallVectorImpl : public SmallVectorTemplateBase<T> {
+	using SuperClass = SmallVectorTemplateBase<T>;
+
+public:
+	using iterator = typename SuperClass::iterator;
+	using const_iterator = typename SuperClass::const_iterator;
+	using reference = typename SuperClass::reference;
+	using size_type = typename SuperClass::size_type;
+
+protected:
+	using SmallVectorTemplateBase<T>::TakesParamByValue;
+	using ValueParamT = typename SuperClass::ValueParamT;
+
+	// Default ctor - Initialize to empty.
+	explicit SmallVectorImpl(unsigned N)
+		: SmallVectorTemplateBase<T>(N) {}
+
+	void assignRemote(SmallVectorImpl&& RHS) {
+		this->destroy_range(this->begin(), this->end());
+		if (!this->isSmall())
+			free(this->begin());
+		this->BeginX = RHS.BeginX;
+		this->Size = RHS.Size;
+		this->Capacity = RHS.Capacity;
+		RHS.resetToSmall();
+	}
+
+public:
+	SmallVectorImpl(const SmallVectorImpl&) = delete;
+
+	~SmallVectorImpl() {
+		// Subclass has already destructed this vector's elements.
+		// If this wasn't grown from the inline copy, deallocate the old space.
+		if (!this->isSmall())
+			free(this->begin());
+	}
+
+	void clear() {
+		this->destroy_range(this->begin(), this->end());
+		this->Size = 0;
+	}
+
+private:
+	// Make set_size() private to avoid misuse in subclasses.
+	using SuperClass::set_size;
+
+	template <bool ForOverwrite>
+	void resizeImpl(size_type N) {
+		if (N == this->size())
+			return;
+
+		if (N < this->size()) {
+			this->truncate(N);
+			return;
+		}
+
+		this->reserve(N);
+		for (auto I = this->end(), E = this->begin() + N; I != E; ++I)
+			if (ForOverwrite)
+				new (&*I) T;
+			else
+				new (&*I) T();
+		this->set_size(N);
+	}
+
+public:
+	void resize(size_type N) { resizeImpl<false>(N); }
+
+	/// Like resize, but \ref T is POD, the new values won't be initialized.
+	void resize_for_overwrite(size_type N) { resizeImpl<true>(N); }
+
+	/// Like resize, but requires that \p N is less than \a size().
+	void truncate(size_type N) {
+		assert(this->size() >= N && "Cannot increase size with truncate");
+		this->destroy_range(this->begin() + N, this->end());
+		this->set_size(N);
+	}
+
+	void resize(size_type N, ValueParamT NV) {
+		if (N == this->size())
+			return;
+
+		if (N < this->size()) {
+			this->truncate(N);
+			return;
+		}
+
+		// N > this->size(). Defer to append.
+		this->append(N - this->size(), NV);
+	}
+
+	void reserve(size_type N) {
+		if (this->capacity() < N)
+			this->grow(N);
+	}
+
+	void pop_back_n(size_type NumItems) {
+		assert(this->size() >= NumItems);
+		truncate(this->size() - NumItems);
+	}
+
+	[[nodiscard]] T pop_back_val() {
+		T Result = ::std::move(this->back());
+		this->pop_back();
+		return Result;
+	}
+
+	void swap(SmallVectorImpl& RHS);
+
+	/// Add the specified range to the end of the SmallVector.
+	template <typename in_iter,
+		typename = std::enable_if_t<std::is_convertible<
+			typename std::iterator_traits<in_iter>::iterator_category,
+			std::input_iterator_tag>::value>>
+	void append(in_iter in_start, in_iter in_end) {
+		this->assertSafeToAddRange(in_start, in_end);
+		size_type NumInputs = std::distance(in_start, in_end);
+		this->reserve(this->size() + NumInputs);
+		this->uninitialized_copy(in_start, in_end, this->end());
+		this->set_size(this->size() + NumInputs);
+	}
+
+	/// Append \p NumInputs copies of \p Elt to the end.
+	void append(size_type NumInputs, ValueParamT Elt) {
+		const T* EltPtr = this->reserveForParamAndGetAddress(Elt, NumInputs);
+		std::uninitialized_fill_n(this->end(), NumInputs, *EltPtr);
+		this->set_size(this->size() + NumInputs);
+	}
+
+	void append(std::initializer_list<T> IL) {
+		append(IL.begin(), IL.end());
+	}
+
+	void append(const SmallVectorImpl& RHS) { append(RHS.begin(), RHS.end()); }
+
+	void assign(size_type NumElts, ValueParamT Elt) {
+		// Note that Elt could be an internal reference.
+		if (NumElts > this->capacity()) {
+			this->growAndAssign(NumElts, Elt);
+			return;
+		}
+
+		// Assign over existing elements.
+		std::fill_n(this->begin(), std::min(NumElts, this->size()), Elt);
+		if (NumElts > this->size())
+			std::uninitialized_fill_n(this->end(), NumElts - this->size(), Elt);
+		else if (NumElts < this->size())
+			this->destroy_range(this->begin() + NumElts, this->end());
+		this->set_size(NumElts);
+	}
+
+	// FIXME: Consider assigning over existing elements, rather than clearing &
+	// re-initializing them - for all assign(...) variants.
+
+	template <typename in_iter,
+		typename = std::enable_if_t<std::is_convertible<
+			typename std::iterator_traits<in_iter>::iterator_category,
+			std::input_iterator_tag>::value>>
+	void assign(in_iter in_start, in_iter in_end) {
+		this->assertSafeToReferenceAfterClear(in_start, in_end);
+		clear();
+		append(in_start, in_end);
+	}
+
+	void assign(std::initializer_list<T> IL) {
+		clear();
+		append(IL);
+	}
+
+	void assign(const SmallVectorImpl& RHS) { assign(RHS.begin(), RHS.end()); }
+
+	iterator erase(const_iterator CI) {
+		// Just cast away constness because this is a non-const member function.
+		iterator I = const_cast<iterator>(CI);
+
+		assert(this->isReferenceToStorage(CI) && "Iterator to erase is out of bounds.");
+
+		iterator N = I;
+		// Shift all elts down one.
+		std::move(I + 1, this->end(), I);
+		// Drop the last elt.
+		this->pop_back();
+		return (N);
+	}
+
+	iterator erase(const_iterator CS, const_iterator CE) {
+		// Just cast away constness because this is a non-const member function.
+		iterator S = const_cast<iterator>(CS);
+		iterator E = const_cast<iterator>(CE);
+
+		assert(this->isRangeInStorage(S, E) && "Range to erase is out of bounds.");
+
+		iterator N = S;
+		// Shift all elts down.
+		iterator I = std::move(E, this->end(), S);
+		// Drop the last elts.
+		this->destroy_range(I, this->end());
+		this->set_size(I - this->begin());
+		return (N);
+	}
+
+private:
+	template <class ArgType>
+	iterator insert_one_impl(iterator I, ArgType&& Elt) {
+		// Callers ensure that ArgType is derived from T.
+		static_assert(
+			std::is_same<std::remove_const_t<std::remove_reference_t<ArgType>>,
+				T>::value,
+			"ArgType must be derived from T!");
+
+		if (I == this->end()) { // Important special case for empty vector.
+			this->push_back(::std::forward<ArgType>(Elt));
+			return this->end() - 1;
+		}
+
+		assert(this->isReferenceToStorage(I) && "Insertion iterator is out of bounds.");
+
+		// Grow if necessary.
+		size_t Index = I - this->begin();
+		std::remove_reference_t<ArgType>* EltPtr =
+			this->reserveForParamAndGetAddress(Elt);
+		I = this->begin() + Index;
+
+		::new ((void*)this->end()) T(::std::move(this->back()));
+		// Push everything else over.
+		std::move_backward(I, this->end() - 1, this->end());
+		this->set_size(this->size() + 1);
+
+		// If we just moved the element we're inserting, be sure to update
+		// the reference (never happens if TakesParamByValue).
+		static_assert(!TakesParamByValue || std::is_same<ArgType, T>::value,
+			"ArgType must be 'T' when taking by value!");
+		if (!TakesParamByValue && this->isReferenceToRange(EltPtr, I, this->end()))
+			++EltPtr;
+
+		*I = ::std::forward<ArgType>(*EltPtr);
+		return I;
+	}
+
+public:
+	iterator insert(iterator I, T&& Elt) {
+		return insert_one_impl(I, this->forward_value_param(std::move(Elt)));
+	}
+
+	iterator insert(iterator I, const T& Elt) {
+		return insert_one_impl(I, this->forward_value_param(Elt));
+	}
+
+	iterator insert(iterator I, size_type NumToInsert, ValueParamT Elt) {
+		// Convert iterator to elt# to avoid invalidating iterator when we reserve()
+		size_t InsertElt = I - this->begin();
+
+		if (I == this->end()) { // Important special case for empty vector.
+			append(NumToInsert, Elt);
+			return this->begin() + InsertElt;
+		}
+
+		assert(this->isReferenceToStorage(I) && "Insertion iterator is out of bounds.");
+
+		// Ensure there is enough space, and get the (maybe updated) address of
+		// Elt.
+		const T* EltPtr = this->reserveForParamAndGetAddress(Elt, NumToInsert);
+
+		// Uninvalidate the iterator.
+		I = this->begin() + InsertElt;
+
+		// If there are more elements between the insertion point and the end of the
+		// range than there are being inserted, we can use a simple approach to
+		// insertion.  Since we already reserved space, we know that this won't
+		// reallocate the vector.
+		if (size_t(this->end() - I) >= NumToInsert) {
+			T* OldEnd = this->end();
+			append(std::move_iterator<iterator>(this->end() - NumToInsert),
+				std::move_iterator<iterator>(this->end()));
+
+			// Copy the existing elements that get replaced.
+			std::move_backward(I, OldEnd - NumToInsert, OldEnd);
+
+			// If we just moved the element we're inserting, be sure to update
+			// the reference (never happens if TakesParamByValue).
+			if (!TakesParamByValue && I <= EltPtr && EltPtr < this->end())
+				EltPtr += NumToInsert;
+
+			std::fill_n(I, NumToInsert, *EltPtr);
+			return I;
+		}
+
+		// Otherwise, we're inserting more elements than exist already, and we're
+		// not inserting at the end.
+
+		// Move over the elements that we're about to overwrite.
+		T* OldEnd = this->end();
+		this->set_size(this->size() + NumToInsert);
+		size_t NumOverwritten = OldEnd - I;
+		this->uninitialized_move(I, OldEnd, this->end() - NumOverwritten);
+
+		// If we just moved the element we're inserting, be sure to update
+		// the reference (never happens if TakesParamByValue).
+		if (!TakesParamByValue && I <= EltPtr && EltPtr < this->end())
+			EltPtr += NumToInsert;
+
+		// Replace the overwritten part.
+		std::fill_n(I, NumOverwritten, *EltPtr);
+
+		// Insert the non-overwritten middle part.
+		std::uninitialized_fill_n(OldEnd, NumToInsert - NumOverwritten, *EltPtr);
+		return I;
+	}
+
+	template <typename ItTy,
+		typename = std::enable_if_t<std::is_convertible<
+			typename std::iterator_traits<ItTy>::iterator_category,
+			std::input_iterator_tag>::value>>
+	iterator insert(iterator I, ItTy From, ItTy To) {
+		// Convert iterator to elt# to avoid invalidating iterator when we reserve()
+		size_t InsertElt = I - this->begin();
+
+		if (I == this->end()) { // Important special case for empty vector.
+			append(From, To);
+			return this->begin() + InsertElt;
+		}
+
+		assert(this->isReferenceToStorage(I) && "Insertion iterator is out of bounds.");
+
+		// Check that the reserve that follows doesn't invalidate the iterators.
+		this->assertSafeToAddRange(From, To);
+
+		size_t NumToInsert = std::distance(From, To);
+
+		// Ensure there is enough space.
+		reserve(this->size() + NumToInsert);
+
+		// Uninvalidate the iterator.
+		I = this->begin() + InsertElt;
+
+		// If there are more elements between the insertion point and the end of the
+		// range than there are being inserted, we can use a simple approach to
+		// insertion.  Since we already reserved space, we know that this won't
+		// reallocate the vector.
+		if (size_t(this->end() - I) >= NumToInsert) {
+			T* OldEnd = this->end();
+			append(std::move_iterator<iterator>(this->end() - NumToInsert),
+				std::move_iterator<iterator>(this->end()));
+
+			// Copy the existing elements that get replaced.
+			std::move_backward(I, OldEnd - NumToInsert, OldEnd);
+
+			std::copy(From, To, I);
+			return I;
+		}
+
+		// Otherwise, we're inserting more elements than exist already, and we're
+		// not inserting at the end.
+
+		// Move over the elements that we're about to overwrite.
+		T* OldEnd = this->end();
+		this->set_size(this->size() + NumToInsert);
+		size_t NumOverwritten = OldEnd - I;
+		this->uninitialized_move(I, OldEnd, this->end() - NumOverwritten);
+
+		// Replace the overwritten part.
+		for (T* J = I; NumOverwritten > 0; --NumOverwritten) {
+			*J = *From;
+			++J;
+			++From;
+		}
+
+		// Insert the non-overwritten middle part.
+		this->uninitialized_copy(From, To, OldEnd);
+		return I;
+	}
+
+	void insert(iterator I, std::initializer_list<T> IL) {
+		insert(I, IL.begin(), IL.end());
+	}
+
+	template <typename... ArgTypes>
+	reference emplace_back(ArgTypes&&... Args) {
+		if (LLVM_UNLIKELY(this->size() >= this->capacity()))
+			return this->growAndEmplaceBack(std::forward<ArgTypes>(Args)...);
+
+		::new ((void*)this->end()) T(std::forward<ArgTypes>(Args)...);
+		this->set_size(this->size() + 1);
+		return this->back();
+	}
+
+	SmallVectorImpl& operator=(const SmallVectorImpl& RHS);
+
+	SmallVectorImpl& operator=(SmallVectorImpl&& RHS);
+
+	bool operator==(const SmallVectorImpl& RHS) const {
+		if (this->size() != RHS.size()) return false;
+		return std::equal(this->begin(), this->end(), RHS.begin());
+	}
+	bool operator!=(const SmallVectorImpl& RHS) const {
+		return !(*this == RHS);
+	}
+
+	bool operator<(const SmallVectorImpl& RHS) const {
+		return std::lexicographical_compare(this->begin(), this->end(), RHS.begin(), RHS.end());
+	}
+};
+
+template <typename T>
+void SmallVectorImpl<T>::swap(SmallVectorImpl<T>& RHS) {
+	if (this == &RHS) return;
+
+	// We can only avoid copying elements if neither vector is small.
+	if (!this->isSmall() && !RHS.isSmall()) {
+		std::swap(this->BeginX, RHS.BeginX);
+		std::swap(this->Size, RHS.Size);
+		std::swap(this->Capacity, RHS.Capacity);
+		return;
+	}
+	this->reserve(RHS.size());
+	RHS.reserve(this->size());
+
+	// Swap the shared elements.
+	size_t NumShared = this->size();
+	if (NumShared > RHS.size()) NumShared = RHS.size();
+	for (size_type i = 0; i != NumShared; ++i)
+		std::swap((*this)[i], RHS[i]);
+
+	// Copy over the extra elts.
+	if (this->size() > RHS.size()) {
+		size_t EltDiff = this->size() - RHS.size();
+		this->uninitialized_copy(this->begin() + NumShared, this->end(), RHS.end());
+		RHS.set_size(RHS.size() + EltDiff);
+		this->destroy_range(this->begin() + NumShared, this->end());
+		this->set_size(NumShared);
+	} else if (RHS.size() > this->size()) {
+		size_t EltDiff = RHS.size() - this->size();
+		this->uninitialized_copy(RHS.begin() + NumShared, RHS.end(), this->end());
+		this->set_size(this->size() + EltDiff);
+		this->destroy_range(RHS.begin() + NumShared, RHS.end());
+		RHS.set_size(NumShared);
+	}
+}
+
+template <typename T>
+SmallVectorImpl<T>& SmallVectorImpl<T>::
+operator=(const SmallVectorImpl<T>& RHS) {
+	// Avoid self-assignment.
+	if (this == &RHS) return *this;
+
+	// If we already have sufficient space, assign the common elements, then
+	// destroy any excess.
+	size_t RHSSize = RHS.size();
+	size_t CurSize = this->size();
+	if (CurSize >= RHSSize) {
+		// Assign common elements.
+		iterator NewEnd;
+		if (RHSSize)
+			NewEnd = std::copy(RHS.begin(), RHS.begin() + RHSSize, this->begin());
+		else
+			NewEnd = this->begin();
+
+		// Destroy excess elements.
+		this->destroy_range(NewEnd, this->end());
+
+		// Trim.
+		this->set_size(RHSSize);
+		return *this;
+	}
+
+	// If we have to grow to have enough elements, destroy the current elements.
+	// This allows us to avoid copying them during the grow.
+	// FIXME: don't do this if they're efficiently moveable.
+	if (this->capacity() < RHSSize) {
+		// Destroy current elements.
+		this->clear();
+		CurSize = 0;
+		this->grow(RHSSize);
+	} else if (CurSize) {
+		// Otherwise, use assignment for the already-constructed elements.
+		std::copy(RHS.begin(), RHS.begin() + CurSize, this->begin());
+	}
+
+	// Copy construct the new elements in place.
+	this->uninitialized_copy(RHS.begin() + CurSize, RHS.end(), this->begin() + CurSize);
+
+	// Set end.
+	this->set_size(RHSSize);
+	return *this;
+}
+
+template <typename T>
+SmallVectorImpl<T>& SmallVectorImpl<T>::operator=(SmallVectorImpl<T>&& RHS) {
+	// Avoid self-assignment.
+	if (this == &RHS) return *this;
+
+	// If the RHS isn't small, clear this vector and then steal its buffer.
+	if (!RHS.isSmall()) {
+		this->assignRemote(std::move(RHS));
+		return *this;
+	}
+
+	// If we already have sufficient space, assign the common elements, then
+	// destroy any excess.
+	size_t RHSSize = RHS.size();
+	size_t CurSize = this->size();
+	if (CurSize >= RHSSize) {
+		// Assign common elements.
+		iterator NewEnd = this->begin();
+		if (RHSSize)
+			NewEnd = std::move(RHS.begin(), RHS.end(), NewEnd);
+
+		// Destroy excess elements and trim the bounds.
+		this->destroy_range(NewEnd, this->end());
+		this->set_size(RHSSize);
+
+		// Clear the RHS.
+		RHS.clear();
+
+		return *this;
+	}
+
+	// If we have to grow to have enough elements, destroy the current elements.
+	// This allows us to avoid copying them during the grow.
+	// FIXME: this may not actually make any sense if we can efficiently move
+	// elements.
+	if (this->capacity() < RHSSize) {
+		// Destroy current elements.
+		this->clear();
+		CurSize = 0;
+		this->grow(RHSSize);
+	} else if (CurSize) {
+		// Otherwise, use assignment for the already-constructed elements.
+		std::move(RHS.begin(), RHS.begin() + CurSize, this->begin());
+	}
+
+	// Move-construct the new elements in place.
+	this->uninitialized_move(RHS.begin() + CurSize, RHS.end(), this->begin() + CurSize);
+
+	// Set end.
+	this->set_size(RHSSize);
+
+	RHS.clear();
+	return *this;
+}
+
+/// Storage for the SmallVector elements.  This is specialized for the N=0 case
+/// to avoid allocating unnecessary storage.
+template <typename T, unsigned N>
+struct SmallVectorStorage {
+	alignas(T) char InlineElts[N * sizeof(T)];
+};
+
+/// We need the storage to be properly aligned even for small-size of 0 so that
+/// the pointer math in \a SmallVectorTemplateCommon::getFirstEl() is
+/// well-defined.
+template <typename T>
+struct alignas(T) SmallVectorStorage<T, 0> {};
+
+/// Forward declaration of SmallVector so that
+/// calculateSmallVectorDefaultInlinedElements can reference
+/// `sizeof(SmallVector<T, 0>)`.
+template <typename T, unsigned N>
+class SmallVector;
+
+/// Helper class for calculating the default number of inline elements for
+/// `SmallVector<T>`.
+///
+/// This should be migrated to a constexpr function when our minimum
+/// compiler support is enough for multi-statement constexpr functions.
+template <typename T>
+struct CalculateSmallVectorDefaultInlinedElements {
+	// Parameter controlling the default number of inlined elements
+	// for `SmallVector<T>`.
+	//
+	// The default number of inlined elements ensures that
+	// 1. There is at least one inlined element.
+	// 2. `sizeof(SmallVector<T>) <= kPreferredSmallVectorSizeof` unless
+	// it contradicts 1.
+	static constexpr size_t kPreferredSmallVectorSizeof = 64;
+
+	// static_assert that sizeof(T) is not "too big".
+	//
+	// Because our policy guarantees at least one inlined element, it is possible
+	// for an arbitrarily large inlined element to allocate an arbitrarily large
+	// amount of inline storage. We generally consider it an antipattern for a
+	// SmallVector to allocate an excessive amount of inline storage, so we want
+	// to call attention to these cases and make sure that users are making an
+	// intentional decision if they request a lot of inline storage.
+	//
+	// We want this assertion to trigger in pathological cases, but otherwise
+	// not be too easy to hit. To accomplish that, the cutoff is actually somewhat
+	// larger than kPreferredSmallVectorSizeof (otherwise,
+	// `SmallVector<SmallVector<T>>` would be one easy way to trip it, and that
+	// pattern seems useful in practice).
+	//
+	// One wrinkle is that this assertion is in theory non-portable, since
+	// sizeof(T) is in general platform-dependent. However, we don't expect this
+	// to be much of an issue, because most LLVM development happens on 64-bit
+	// hosts, and therefore sizeof(T) is expected to *decrease* when compiled for
+	// 32-bit hosts, dodging the issue. The reverse situation, where development
+	// happens on a 32-bit host and then fails due to sizeof(T) *increasing* on a
+	// 64-bit host, is expected to be very rare.
+	static_assert(
+		sizeof(T) <= 256,
+		"You are trying to use a default number of inlined elements for "
+		"`SmallVector<T>` but `sizeof(T)` is really big! Please use an "
+		"explicit number of inlined elements with `SmallVector<T, N>` to make "
+		"sure you really want that much inline storage.");
+
+	// Discount the size of the header itself when calculating the maximum inline
+	// bytes.
+	static constexpr size_t PreferredInlineBytes =
+		kPreferredSmallVectorSizeof - sizeof(SmallVector<T, 0>);
+	static constexpr size_t NumElementsThatFit = PreferredInlineBytes / sizeof(T);
+	static constexpr size_t value =
+		NumElementsThatFit == 0 ? 1 : NumElementsThatFit;
+};
+
+/// This is a 'vector' (really, a variable-sized array), optimized
+/// for the case when the array is small.  It contains some number of elements
+/// in-place, which allows it to avoid heap allocation when the actual number of
+/// elements is below that threshold.  This allows normal "small" cases to be
+/// fast without losing generality for large inputs.
+///
+/// \note
+/// In the absence of a well-motivated choice for the number of inlined
+/// elements \p N, it is recommended to use \c SmallVector<T> (that is,
+/// omitting the \p N). This will choose a default number of inlined elements
+/// reasonable for allocation on the stack (for example, trying to keep \c
+/// sizeof(SmallVector<T>) around 64 bytes).
+///
+/// \warning This does not attempt to be exception safe.
+///
+/// \see https://llvm.org/docs/ProgrammersManual.html#llvm-adt-smallvector-h
+template <typename T,
+	unsigned N = CalculateSmallVectorDefaultInlinedElements<T>::value>
+class SmallVector : public SmallVectorImpl<T>,
+					SmallVectorStorage<T, N> {
+public:
+	SmallVector()
+		: SmallVectorImpl<T>(N) {}
+
+	~SmallVector() {
+		// Destroy the constructed elements in the vector.
+		this->destroy_range(this->begin(), this->end());
+	}
+
+	explicit SmallVector(size_t Size, const T& Value = T())
+		: SmallVectorImpl<T>(N) {
+		this->assign(Size, Value);
+	}
+
+	template <typename ItTy,
+		typename = std::enable_if_t<std::is_convertible<
+			typename std::iterator_traits<ItTy>::iterator_category,
+			std::input_iterator_tag>::value>>
+	SmallVector(ItTy S, ItTy E)
+		: SmallVectorImpl<T>(N) {
+		this->append(S, E);
+	}
+
+	template <typename RangeTy>
+	explicit SmallVector(const iterator_range<RangeTy>& R)
+		: SmallVectorImpl<T>(N) {
+		this->append(R.begin(), R.end());
+	}
+
+	SmallVector(std::initializer_list<T> IL)
+		: SmallVectorImpl<T>(N) {
+		this->assign(IL);
+	}
+
+	SmallVector(const SmallVector& RHS)
+		: SmallVectorImpl<T>(N) {
+		if (!RHS.empty())
+			SmallVectorImpl<T>::operator=(RHS);
+	}
+
+	SmallVector& operator=(const SmallVector& RHS) {
+		SmallVectorImpl<T>::operator=(RHS);
+		return *this;
+	}
+
+	SmallVector(SmallVector&& RHS)
+		: SmallVectorImpl<T>(N) {
+		if (!RHS.empty())
+			SmallVectorImpl<T>::operator=(::std::move(RHS));
+	}
+
+	SmallVector(SmallVectorImpl<T>&& RHS)
+		: SmallVectorImpl<T>(N) {
+		if (!RHS.empty())
+			SmallVectorImpl<T>::operator=(::std::move(RHS));
+	}
+
+	SmallVector& operator=(SmallVector&& RHS) {
+		if (N) {
+			SmallVectorImpl<T>::operator=(::std::move(RHS));
+			return *this;
+		}
+		// SmallVectorImpl<T>::operator= does not leverage N==0. Optimize the
+		// case.
+		if (this == &RHS)
+			return *this;
+		if (RHS.empty()) {
+			this->destroy_range(this->begin(), this->end());
+			this->Size = 0;
+		} else {
+			this->assignRemote(std::move(RHS));
+		}
+		return *this;
+	}
+
+	SmallVector& operator=(SmallVectorImpl<T>&& RHS) {
+		SmallVectorImpl<T>::operator=(::std::move(RHS));
+		return *this;
+	}
+
+	SmallVector& operator=(std::initializer_list<T> IL) {
+		this->assign(IL);
+		return *this;
+	}
+};
+
+template <typename T, unsigned N>
+inline size_t capacity_in_bytes(const SmallVector<T, N>& X) {
+	return X.capacity_in_bytes();
+}
+
+template <typename RangeType>
+using ValueTypeFromRangeType =
+	typename std::remove_const<typename std::remove_reference<
+		decltype(*std::begin(std::declval<RangeType&>()))>::type>::type;
+
+/// Given a range of type R, iterate the entire range and return a
+/// SmallVector with elements of the vector.  This is useful, for example,
+/// when you want to iterate a range and then sort the results.
+template <unsigned Size, typename R>
+SmallVector<ValueTypeFromRangeType<R>, Size> to_vector(R&& Range) {
+	return { std::begin(Range), std::end(Range) };
+}
+template <typename R>
+SmallVector<ValueTypeFromRangeType<R>,
+	CalculateSmallVectorDefaultInlinedElements<
+		ValueTypeFromRangeType<R>>::value>
+to_vector(R&& Range) {
+	return { std::begin(Range), std::end(Range) };
+}
+
+namespace std {
+
+/// Implement std::swap in terms of SmallVector swap.
+template <typename T>
+inline void swap(SmallVectorImpl<T>& LHS, SmallVectorImpl<T>& RHS) {
+	LHS.swap(RHS);
+}
+
+/// Implement std::swap in terms of SmallVector swap.
+template <typename T, unsigned N>
+inline void swap(SmallVector<T, N>& LHS, SmallVector<T, N>& RHS) {
+	LHS.swap(RHS);
+}
+
+} // namespace std
+
+#ifdef _MSC_VER
+#	pragma warning(pop)
+#endif
diff --git a/source-common/TypeTraits.hpp b/source-common/TypeTraits.hpp
new file mode 100644
index 0000000..cca9a1f
--- /dev/null
+++ b/source-common/TypeTraits.hpp
@@ -0,0 +1,19 @@
+#pragma once
+
+template <class T>
+struct DefaultDeleter {
+    void operator()(T* ptr) const {
+        delete ptr;
+    }
+};
+
+template <class>
+struct RemoveMemberPtrImpl {};
+
+template <class T, class U>
+struct RemoveMemberPtrImpl<U T::*> {
+    using Type = U;
+};
+
+template <class T>
+using RemoveMemberPtr = typename RemoveMemberPtrImpl<T>::Type;
diff --git a/source-common/Uid.cpp b/source-common/Uid.cpp
new file mode 100644
index 0000000..1930cd8
--- /dev/null
+++ b/source-common/Uid.cpp
@@ -0,0 +1,58 @@
+#include "Uid.hpp"
+
+#include "RapidJsonHelper.hpp"
+
+#include <rapidjson/document.h>
+#include <cstring>
+#include <random>
+
+Uid Uid::Create() {
+	std::random_device rd;
+	std::mt19937_64 gen(rd());
+	std::uniform_int_distribution<uint64_t> dist(
+		std::numeric_limits<uint64_t>::min(),
+		std::numeric_limits<uint64_t>::max());
+
+	Uid uid;
+	uid.upper = dist(gen);
+	uid.lower = dist(gen);
+	return uid;
+}
+
+bool Uid::IsNull() const {
+	return upper == 0 && lower == 0;
+}
+
+void Uid::ReadString(std::string_view str) {
+	sscanf(str.data(), BRUSSEL_Uid_SCAN_STR, &upper, &lower);
+}
+
+std::string Uid::WriteString() {
+	char buf[256];
+	snprintf(buf, sizeof(buf), BRUSSEL_Uid_FORMAT_STR, upper, lower);
+	return std::string(buf);
+}
+
+void Uid::Read(const rapidjson::Value& value) {
+	assert(value.IsArray());
+	assert(value.Size() == 2);
+	auto& upper = value[0];
+	assert(upper.IsUint64());
+	auto& lower = value[1];
+	assert(lower.IsUint64());
+
+	this->upper = upper.GetUint64();
+	this->lower = lower.GetUint64();
+}
+
+void Uid::WriteInto(rapidjson::Value& value, rapidjson::Document& root) {
+	value.Reserve(2, root.GetAllocator());
+	value.PushBack((uint64_t)upper, root.GetAllocator());
+	value.PushBack((uint64_t)lower, root.GetAllocator());
+}
+
+rapidjson::Value Uid::Write(rapidjson::Document& root) {
+	rapidjson::Value result(rapidjson::kArrayType);
+	WriteInto(result, root);
+	return result;
+}
diff --git a/source-common/Uid.hpp b/source-common/Uid.hpp
new file mode 100644
index 0000000..f58129c
--- /dev/null
+++ b/source-common/Uid.hpp
@@ -0,0 +1,42 @@
+#pragma once
+
+#include "Utils.hpp"
+
+#include <rapidjson/fwd.h>
+#include <cinttypes>
+#include <functional>
+#include <string>
+#include <string_view>
+
+#define BRUSSEL_Uid_SCAN_STR "%" PRIx64 "-%" PRIx64
+#define BRUSSEL_Uid_SCAN_EXPAND(uid) &((uid).upper), &((uid).upper)
+#define BRUSSEL_Uid_FORMAT_STR "%016" PRIx64 "-%016" PRIx64
+#define BRUSSEL_Uid_FORMAT_EXPAND(uid) (uid).upper, (uid).lower
+
+struct Uid {
+	uint64_t upper = 0;
+	uint64_t lower = 0;
+
+	static Uid Create();
+
+	bool IsNull() const;
+
+	void ReadString(std::string_view str);
+	std::string WriteString();
+
+	void Read(const rapidjson::Value& value);
+	void WriteInto(rapidjson::Value& value, rapidjson::Document& root);
+	rapidjson::Value Write(rapidjson::Document& root);
+
+	auto operator<=>(const Uid&) const = default;
+};
+
+template <>
+struct std::hash<Uid> {
+	size_t operator()(const Uid& uid) const {
+		size_t hash = 0;
+		Utils::HashCombine(hash, uid.upper);
+		Utils::HashCombine(hash, uid.lower);
+		return hash;
+	}
+};